1. Field
Embodiments described herein relate generally to a semiconductor memory device.
2. Background Art
In the prior art, there is a semiconductor memory device comprising a plurality of basic cells which immobilize the structure of a transistor. Then, by modifying the metal layer or the via layer, etc. are connected to the plurality of basic cells, and correspond to different operating requirements or circuit requirements of the semiconductor memory device without modifying the basic cell portion.
In the semiconductor memory device having a plurality of input and output ports, when applying the above conventional technique uses a semiconductor memory device having a maximum output ports to need as the basic cell.
However, in a typical semiconductor memory device, the number of input and output ports is increased in order to increase the area. Therefore, if a large number of ports are not used, the semiconductor memory device provides unnecessary circuits, a reduction in circuit area are not achieved.